Services, Grounding & BondingCâu 58 / 120
A dry-type transformer rated 112.5 kVA or less is installed indoors. What is the minimum separation from combustible material unless it is separated by a fire-resistant heat-insulating barrier?
a.3 inches
b.6 inches
c.12 inches
d.18 inches
Giải thích
Dry-type transformers of 112.5 kVA or less must be at least 12 inches from combustible material unless separated by a fire-resistant, heat-insulating barrier or unless the unit is completely enclosed except for ventilating openings. The smaller clearances listed belong to other rules such as recessed luminaire and insulation spacing, not to transformer installation.
Trích dẫn luật: 2023 NEC §450.21(A)Luyện miễn phí toàn bộ 120 câu hỏi — không cần đăng ký.
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